This service which is still under experiment will undergo a test where a few users in the US will be trying out the commercial service starting today October 24.

Operamini browser also did something similar to this when they introduced a free VPN service for users of their browser. This VPN service will protect Firefox browser from insecure connection, harmful websites and many other things a VPN has to offer.

"Our core mission is protecting privacy and security online," Proton VPN said in a blog post. "Mozilla, the creator of Firefox, strongly aligns with this mission and we're proud to partner with them to help more people stay safe."

While the Operamini VPN service was free, the ProtonVPN service which will be served via Firefox goes for $10 per month. The selling of this VPN service through the Firefox browser will generate some revenue for Mozilla.

Firefox will recommend the VPN service to her users. For example, Firefox users browsing the web on an unsecured wireless network will get this pop-up from Firefox: "Firefox recommends ProtonVPN, it appears you are browsing on an unsecured wireless network. Firefox has teamed up with ProtonVPN to provide you with a private and secure Internet connection. No matter where you are."

This service once subscribed to, can be accessed by the user through Windows, Linux, iOS, Android and macOS. And also, the VPN can be easily turned off, and the subscription easily canceled at any time.

Explaining via a blog post why ProtonVPN was chosen as the first advertise on Firefox, Mozilla said:

"Our team looked closely at a wide variety of factors, ranging from design and implementation of each VPN service and its accompanying software, to the security of the vendor's own network and internal systems. We examined each vendors privacy and data retention policies to ensure they logged as little user data as possible. And we considered numerous other factors, including local privacy laws, company track record, transparency, and quality of support."

For now, this VPN service is available for few individuals who are still testing the service. If the experiment goes well, the service will be made available to Firefox users who are over 300 million in the world.